This is a competing renewal application for a prospective study of oral health and dental care called the Florida Dental Care Study (FDCS). The FDCS sample is diverse, including many subjects at increased risk for oral health disparities (e.g., Blacks, persons of low socioeconomic status (SES), irregular dental attenders). So far, we have tested important hypotheses about the relationship between dental disease measured clinically, self-reported dimensions of oral health, health-related quality of life, and use of dental care. The FDCS has been highly productive, with many novel findings, and logistically successful (e.g., low attrition). However, despite 40 journal articles/manuscripts so far, an historical opportunity exists to capitalize on a unique database that is unprecedented in adult oral health disparities research, oral epidemiology, and dental health services research. As a result of our proposed new focus in this application on health disparities, we expect that many of the yet-to-be-analyzed findings will ultimately be judged to be among the most important from the study. Therefore, having recently completed 72 months of data collection, we request funding for two final years focused on oral health disparities. Building upon knowledge gained so far, we now refine and extend our aims to test five key hypotheses about the incidence and chronicity of oral health disparities, as well as the role that incidence of specific dental services plays in oral health disparities. "Disparity" will be defined as an oral health decrement whose incidence or chronicity is significantly higher in the high-risk groups of interest (Blacks, lower SES persons, and irregular attenders). This research will quantify what benefits, or lack thereof, groups at risk for oral health disparities perceive as being derived from their use of dental care, and how this perception affects their use of it. This research is the first study ever to use a certain innovative approach (directly links clinical exam data, self reported dimensions of oral health, use of specific dental services, and diverse patient characteristics) to yield new evidence about incidence and chronicity of oral health disparities in adults, which high-risk sub-groups are at a substantially increased risk (sub-groups defined by potentially modifiable characteristics), why high-risk groups use dental care, and the role that incident dental care plays in health disparities.